Question

A tent is made in the form
of a conic frustum
surmounted by a cone. The
diameter of the base and the
top of the frustum are 14 m
and 7 m and its height is 8 m.
The total height of the tent is
12 m. Find the area of canvas
used to make the tent. (Take
V305 = 17.5 and V113 = 10.6)​

Answer 1

Answer:

Let h be the height of the frustum and r

1

and r

2

be the radii of its circular bases.

We have h=24m,r

1

=10m,r

2

=3m

l= slant height of the frustum

⇒l=

(r

1

−r

2

)

2

+h

2

=

(10−3)

2

+24

2

=25m

for cone VA'B', we have

l

2

= slant height =

O

′

B

′

2

+VO

′

2

=

3

2

+4

2

=5m

Quantity of canvas required

= lateral surface area of frustum + lateral surface area of cone VA

′

B

′

=π(r

1

−r

2

)l+πr

2

l

2

={π(10+3)×25+π×3×5}m

2

=(325π+15π)m

2

=340π m

2